bpf: simplify bpf (device) program freeing

src/lxc/cgroups/cgroup.c

@@ -71,8 +71,7 @@ void cgroup_exit(struct cgroup_ops *ops)
 
 	free_equal(ops->container_cgroup, ops->container_limit_cgroup);
 
-	if (ops->cgroup2_devices)
-		bpf_program_free(ops->cgroup2_devices);
+	bpf_device_program_free(ops);
 
 	if (ops->dfd_mnt_cgroupfs_host >= 0)
 		close(ops->dfd_mnt_cgroupfs_host);

src/lxc/cgroups/cgroup2_devices.c

@@ -60,17 +60,6 @@ static int bpf_program_add_instructions(struct bpf_program *prog,
 	return 0;
 }
 
-void bpf_program_free(struct bpf_program *prog)
-{
-	if (!prog)
-		return;
-
-	(void)bpf_program_cgroup_detach(prog);
-
-	free(prog->instructions);
-	free(prog);
-}
-
 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                               \
 	((struct bpf_insn){.code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \
@@ -442,7 +431,7 @@ void bpf_device_program_free(struct cgroup_ops *ops)
 {
 	if (ops->cgroup2_devices) {
 		(void)bpf_program_cgroup_detach(ops->cgroup2_devices);
-		(void)bpf_program_free(ops->cgroup2_devices);
+		bpf_program_free(ops->cgroup2_devices);
 		ops->cgroup2_devices = NULL;
 	}
 }

src/lxc/cgroups/cgroup2_devices.h

@@ -88,7 +88,6 @@ __hidden extern int bpf_program_init(struct bpf_program *prog);
 __hidden extern int bpf_program_append_device(struct bpf_program *prog, struct device_item *device);
 __hidden extern int bpf_program_finalize(struct bpf_program *prog);
 __hidden extern int bpf_program_cgroup_detach(struct bpf_program *prog);
-__hidden extern void bpf_program_free(struct bpf_program *prog);
 __hidden extern void bpf_device_program_free(struct cgroup_ops *ops);
 __hidden extern bool bpf_devices_cgroup_supported(void);
 
@@ -100,6 +99,14 @@ __hidden extern bool bpf_cgroup_devices_update(struct cgroup_ops *ops,
 					       struct device_item *new,
 					       struct lxc_list *devices);
 
+static inline void bpf_program_free(struct bpf_program *prog)
+{
+	if (prog) {
+		(void)bpf_program_cgroup_detach(prog);
+		free(prog->instructions);
+		free(prog);
+	}
+}
 define_cleanup_function(struct bpf_program *, bpf_program_free);
 #define __do_bpf_program_free call_cleaner(bpf_program_free)